Monitoring device



w. c. ANDERSON Filed Jan. 31, 1948 Fig. 5

3 Sheets-Sheet 2 INVENTOR. WILMER C. ANDERSON Aug. 5, 1952 w. 9 ANDERSON MONITORING DEVICE 3 Sheets-Sheet 3 Filed Jan. 31, 1948 m N m 7 .1 Z; W .0% ,1 Z z 2 a #1] v I q w 1%.-- a a w L 0 00 W i Z; j a ja mm Patented Aug. 5, 1952 f UNITED STAT S PT ENT '9 F F ICE I MONITORING "DEVICE V g Wilmer CsAnderson, Greenwieh-,-Conn.-, assignor to Deering Milliken Research Trust, New York, N 1 a nonprofit trust of New York A Application January 31, 1948, Serial No. 5,580

. I "i c "The present invention relates-to the manufacture of yarn and more particularly to the inspection of yarn for detection and removal of oversized sections therein, and comprises a novel pneumatically operated yarn monitoring device which is simple and economical or construction, positive in action and operates to cause breakage Ofth yarn when the diameter thereof iiceedsia predetermined value over a. predetermined length. The new device does not damage the yarn, can be threaded in one simple operation and quick acting, permitting relatively rapid rate of yarn travel therethrough. The invention includes also a novel method of detecting and signalizing yarn diameter variations.

There are various known mechanical devices, called slub catchers, now in use in the textile industry, each of which operates to cut or break yarn whenever the diameter thereofexceeds a value for which the device is set. In general, these devices respond only to the diameter of the yarnand do not distinguish between slubs of different length. As very short slubs are ordinarily not objectionable, most known devices cut or break'the yarn more often than is necessary.

This results in an excess of knots in the yarn and'in undue labor on the part of the operator who must remove the slub from one end of the yarn after severance by the device and tie the severed ends together. Moreover in the mechani cal slub catchers now in use,-the yarn in its travel constantly engaged by the cutting or breaking'members of the device and hence its surface becomes abraded or roughened during passage through the device.

There has thus been a decided need in the industry for a slub catcher that could distinguish' between long and short slubs and that would not damage the surface of the'yarn. As slub catchers are used at various stages of yarn manufacture, a great number are required in any one mill. Hence, it is of importance that thedevice be of simple ande'conomical construe-- tion, that it operate without failure and math can be easilyandrapidl'y reset and rethreaded,

j The monitor device of the present invention meets these and other desiderata. It discriminates between short and long slubs, allowing the former to pass and oausingbreakage of the yarn upon occurrence of the latter. It is of simple and durable-construction and economical to operate. It'hasno'sharp or roughedgesfor travel ofyarn thereover and hence doesnot damage the yarn.

'Inthe new slub-catchenair', or other compressible "fluid; is delivered under pressurethrough a r 14. Claims. (01,-28-64) restricted passage to a chamber from which it bleeds to the atmosphere through an orifice over which the yarn travels. When the yarn diam"- et'er exceeds a; predetermined value over a ,pre-

determined length, the resulting increase in pres' sure in the chamber operates through a pressure responsive member to trigger a yarn holding element; the diameter of'slub to be caught, and minimum length thereof, depending upon the ad justment of, the triggering element, upon the supply pressure, upon the size of orifice and upon the rate of yarn travel."

For a better understanding of the invention, reference may be had to the accompanying drawin'gs of which:

Fig. l is a top plan view of a pneumatic yarn monitor embodying the invention, 7

Fig. 2 is a front view of the device of Fi '1.

v Figs. 3 and 4 are side views of the device of Fig. 1 looking from the right and left respectively of'Fig. 2, I

Fig. 5 is a sectional view on the line 5-5 of Fig. 2, and

Fig. 6 is a sectional view of an alternative type of pressure head.

In the particular embodiment of the invention'illustrated in Figs. 1 to 5, the various parts of the device are mounted on a base plate 2 which is'sec'ured, as by screw bolts 4 to a bracket 5 for conveni nt mounting on any suitable f xed part of a'winding machine or other mechanism with which the device is' to be used. Two L- shaped support members "8 and ID are positioned respectively above and below the base '2 with one leg of each secured thereto by bolts l2. The other leg? of member '8 supports the pressure responsive element and associated parts of the device now to be described and the other leg I0 of member lfl'supports a conventional yarn guide and'tensioner l4. I

The pressure responsive element comprises a circular diaphragm l6 (see Fig. 5) which is clamped, adjacent its periphery, between a disk l8 and aniannular flange Zilof a cylindrical member 2.2 as .by means of screws 24. Certain of thefscrewsz't pass throu'gh'the leg 8" of supportfijanwserve to secure the cylinder" 22 to the "supportythe' leg 8' being cut away, as's'hown',

ror'jrece tion or the body of the cylinder. The l8 has a central aperture therein which is screw jt'hreaded for i reception of a turnedfdown and 'externallythreaded portion 2a of the yarn gauing head 28; Head 2 8coinprises a generally frustmcoui lmemberf aving, an external anhuammo-Vt '28""for guiding van; in its travel through the device. Portion 26 and the central part of head 28 are reamed out to provide a pressure chamber 30 communicating with one side of diaphragm I6. An air inlet tube 32 extends into a passage 32' in element '28 leading from the face of the element to chamber 30, the tube 32 being press fit and welded or soldered to the wall of the passage or otherwise tightly secured in place so as to prevent leakage of air. The passage 32 and tube 32 are of relatively small cross section so as to offer substantial impedance to the flow of air therethrough. The head 28 is provided with a pair of closely adjacent radial passages 34 of relatively small bore which connect chamber 30 with the annular groove 28' and terminate in orifices 34'. Only one passage 34 appears in the sectional view Fig. 5.

Cylinder 22, is externally threaded for a portion of its length and is provided with a pair of diametrically disposed longitudinal slots 36. An adjusting collar 33 is screw threadedly mounted on the threaded portion of cylinder 22 and a centrally apertured cap 40 is threaded over the end of the cylinder remotefrom the pressure sensitive diaphragm [6. A rod 42 is axially disposed within the cylinder 22 with'one end extending through the aperture in cap 40 and its other end secured to a disk 44 which fits within the cylinder 22 and engages the diaphragm IS. The disk 44 is urged against the diaphragm [6 by a coiled spring 46, one end of which engages the disk 44 and the other end of which engages an annular member 48 within the cylinder. Member 48 has two radial pins 50 secured thereto which extend through the longitudinal slots 36 and engage the collar 38. A lever 52 is pivotally mounted in a yoke 54 rigidlysecured to the cap 40. Lever 52 has an elongated slot 56 therein for reception of the end of rod 42 and has a smaller elongated slot 58 therein intersecting the slot 56 at right angles. A pivot pin 60, extending through the slot 58 and through the rod 42, couples the rod and lever together.

The mechanism triggered in responseto a pre-' determined angular movement of leverf'52 about its pivot resulting from a predetermined increase in pressure in chamber 36 will now be described.

A post 62, mounted on the base 2, pivotally supports a bell crank lever 64 comprising a long arm 64a and a short bifurcated arm 64!). A rod 66, having a relatively heavy end or head 68, is slidably mounted in a pair of spaced supports which extend up from the base 2 and are rigidly securedthereto by screws 12. The rod 66 has a collar 14 adjustably secured thereto which is engaged on one side by thefurcations of arm 64b and on the other side by on'e'end of a compression spring 16; the other end of the spring engaging the rear support 10. Spring 16 thus tends to move rod 66 forwardly into the position illustrated in dotted lines in Fig. 1. Lever 52 is provided with a collar 18 which, in the normal position of lever 52, engages a finger an on the end of arm 64a and prevents clockwise movement (as viewed in Fig. l) of the bellcrank lever 64 and hence, through arm 64b, holds rod 66 in the retracted position indicated in solid lines in Fig. 1. A plate 82"se'cured, as by screws 83,.to. the base 2 serves as a stop for limiting the forward movement of the head 68 of rod66, the upper part of the plate being turned outwardly, as indicated in the drawing, for easy insertion of yarnbetween the hammer 68 and the stop during the threading operation. 'A plate 'or wallfsection 84 secured to the base 2 at right anglesto'the plate 82' has an elongated, partly open sided, slot 84' out there in which serves as a guide for yarn in its exit from the device.

The tension device I4 comprises a pair of bell washers 86 which are rotatably mounted on a rod 88 extending through the leg I0. Light pressure between the washers is provided by a compression spring 90 positioned; about the rod 88 between the rear surface of the. leg I0 and a collar 92 fixed to the rod. A cap 94 on the forward end of rod 88 completes the assembly of the tension device.

Yarn, indicated by the reference numeral 96. travels through the above described slub catcher in the direction indicated by the arrows in Fig. 2. The yarn is supplied from any suitable source and drawn through the device by any suitable take up means; neither the supply nor take up mechanism, being shown in the drawings, as such mechanisms are normal components of mill equipment. Yarn 96 travels between the bell washers 86, makes a quarter turn around the head 28, riding in the groove 28' over the orifices 34', then passe between the hammer 68 andplate B2 and out through the slot 84' in guide 84. "As the path of theyarn includes no closed guide rings or enclosed passages, threading of the .device is simple and rapid, requiring only a looping of a stretch of the yarn around the tension device and head 28 and the insertionof the stretch into the open sided slot 84'. l

During operation of the device,.air utiderjpressure is delivered through the supply'pipe 32 to the chamber 30-, from whence it bleedsto the atmosphere through the passages.34. The yarn,

travelling in the groove 28', passes'jover'the orifices 34 and offers an impedance to the airflow which varies with the yarn diameter." v The parts are so adjusted relativetothe rate'of travel of the yarn, that when the diameterof the yarnoyer. a predetermined length exceeds a predetermined value, say 200 percent of average diameter, the pressure in chamber 36 increases to'a'valu'e suflicient to trip the hammer 68 byrelease of the hold'-.

ing finger the pressureincha'rnbenw acting through diaphragm l6 and, rod 42'to' swing lever 52 outwardly and thereby movei collar [8 out of engagement with finger 86. Whenfinger .80 is released, spring 76 forces hammer 68 intothe dotted line position of Fig. l in'which position the yarn is firmly gripped between the hammer and plate 82. The continuing tension of the take up mechanism causes the yarn to break when so held by the device. Upon breakageof yarn the oper ator removes the oversize section oi yarn, resets.

the device by moving arm 64a into position where finger 80 is engaged by the collar 18, ties the ends of the yarn together and rethreads the device. v

The above described pneumatic slub catcher may be readily adjusted for detection and elimination of slubs of different minimum diameter and length by adjustment of collar 38' to'vary the compression of spring 46. For a. given-rate of travel of the yarn, increase in compression of the spring increases the minimum diameter of a given length of yarn or the minimum lengthof a given diameter of yarn'necessary for tripping the device.

Two closely spaced outlet passages, rather than a single outlet .passage. have been shown in the. drawings, as such construction" reduces the tendency toward turbulence .andhenc is pre-- ferred. In designing the head 28 the passage 32" and tubing 32 are made ofsuch size that the impedance ofier'ed thereby to the 'air now 'will' 'be "substantiallyequal to that offered by the yarn when o'f average diameter so that the normal pressure chamber is substantially half that of the supply pressure. A device constructed in accordance with the above described: embodiment of the invention an having substantially the pro ortions indicated in the drawings has been used satisifactorily to catch slubs in yarn having a cotton count of 12s and travelling at -25 feet persecondl The size of theorinces 34 of such device was 160 1 square inch. With a supply pressure-often pounds per square inch, the device operated to 'catchslulos-in the yarn of over'Onehalf incninlength and of a diamete'r of at least twice the average diameter of the yarn.

The optimum-total cross section of the outlet passages 34 depends upon the average diameter of the yarn't'o be handled. With the constructionillu'strated'in Figs. 1 to 5, thepressurel'iea'd 28 may be readily a head having outlet passages o'f different cross section when yarn-of different average diameter is'to be handled. A'co'nstruction of pressure head which can be 'adjusted for use with yarns of different average diameter is shown in Fig. 6. l 1

- In Fig. 6 the pressure head 233a is-made up of three sectionsQB, Hill and 1'02, which are held tog'ether by a bolt Hi4 passing axially throughportions 1% and H22 and screw threaded into the portion 98; a lead washer its being provided between "the head I 68 of thebolt and the outer surface of portion 162 to 'insure 'a'substantially'airtight fit. An annular flange Ilia of portion'98 is secured, like disk l 80f the construction of Figs. 1 to 5, to the parts'26 aud t of the device by the screws 24; "theidiaphragm it being gripped between the parts 18a and 29. Portion "98 has the pressure chamber Gila formed therein and is provided with a passage l'lflwhich is offset radially. from the axis of the head and alined witha similarly radially offset inlet passage H2 in portion I02 of the head 28a. Portion mo is-provided with a plurality of'radial outlet passages of 'diiferen't cross section of which two, indicatedatl M and H5, appear infthecross section'al view Fig. 6. The'p'or tion Hid-is provided with a number of longitudinal passages 'llS'equal to the'number of outlet passages and adapted'to be individually brought into alinement with the passa'ges llfl and H2 in-portions '98 and wire-- spectively by rotation'of the portion i'il'fl about the common axis of 'the'head 28; each longitudinal'pas'sage I I8 intercepting one radial pas-' sag'e. To-permitrotation of the central portion [60 while preventing rotation of "portion Hi2, a sheath Hills-provided about the bolt Hi l and this sheath is of rectangular cross section at each end whileof circular cross section'for the stretch extending through the portion illil; the sheath fitting into correspondingly shaped airial holes in the three portions of the head; j a Y A'ny suitable means 'maybe' providedfor rotat; ing'the"portion llifito'bring a different outlet passage H8 into alinem lntwithpassages llti'and l i2 when yarn of differentfayeragediameteristo behandled; In the particular construction illus-' trated in Fig. '6, theporti'on I00 is providedon its outer surface with radial cavities ii; for reception of suitable pins or keys by means of which,

when bolt llldis loosened, the portion I69 may be adjusted to'any desiredpositio'n; With this arrangement the smooth contour of the head-28a, making. forieasy threading ofthe devicegis' not disturbed; 1;.

iiilircferabiy, as shown at, .l M; .lsuitable. .idetent removed for replacement by "6 is'provid'ed for insuring proper -alinement-of the passages after angular movement ofthe portion Hill. Any'suitable means, such as the ring seals indicated diagrammatically alt- 126 may -be -pro-- vided :for. preventing 'undue leakage. of air from the device.

From the above description it will be apparent that when portion Hill is in the angular position shown in Fig. 6 and air under pressure is delivered to the inlet passage I I2, outlet'passage I M is connected to the inlet passage and to chamber 35a and hence the pressure acting on the diaphragm It will .be responsive to the diameter of yarn QE,

passing over "the terminal orificeof passage H24. In'this position of the portion 10", the longitudinal passage EH8 communicating with outlet passage H l isin alinement with passages HI! and I I2 but all of the other longitudinal passages l i8 are blockedat their ends by the surfaces of'portions 98 and IE2. When a yarn of a different average diameter .is to be handled, for example,

one .for which the outlet orifice of passage Hi5 is suitable, it .is only necessary to unscrew bolt IM sufficiently topermit relative .rotation of portion we, insert a .pin or key in .a cavity I22 and rotate portion T595 through until the detent I24 slips into the cooperating indentation I24 in the surface of portion liill. :In this position of the parts, a passage H8 will be in communica tion with the air inlet passage and with the chamber Ella and the terminal orifice of passage 1 1'6 will be in the path of travel of the yarn.

The'radial passages of the portion Hill of head could be, and preferably would be, in-pairs, like thepassages 3 of Figs. 1 to 5 as such construction reduces any 'tendency to turbulenceof the emitted air.

The invention has now been described with refcrenceto one specific embodiment thereof and with reference to a modification of -'one part. Obviously, various changes could be made inthe illustrated constructions without departing from thespirit ofthe invention as defined in the apefiicient device wherein-increase in fluidpressure occasioned by a slub in the yarn is utilized {to trip a mechanism which catches or holds the yarn so th'atthe slub may be removed, the yarn itself forming part of a variable orifice through which the fluidjesoapes under pressure to the atmosphere. As the yarn in its travel through the device enga'ges'only smooth rounded surfaces, it is not subjected to wear or damage as in mechanical slub catchers heretofore in .use. Moreover; because tripping of the yarn holding mechanism occursonly when the diameter of a predetermined length of yarn exceeds that desired, short unobjectionable'slubs or nep's will travel through the devicewithout actuation of the hammer, with corresponding conservation of time and labor of the attendant. p

The term yarn in the foregoing description and inthe appended claims is intended to include any textile filamentary material, whether of one or of a plurality of filaments, whether formed of' when the detected impedance exceeds a predetermined value.

2. The method of detecting slubs in yarn which comprises supplying air under pressure through a restricted passage to a chamber from which it may escape through an orifice to the atmosphere, passing yarn over the orifice to vary the pressure in the chamber in accordance with variations in the diameter of the yarn, and arresting the travel of the yarn when the pressure in the chamber exceeds a predetermined value.

3. A device for detecting slubs in yarn comprising in combination an element having a chamber therein and provided with restricted inlet and outlet passages for compressible fluid communicating with said chamber, said outlet passage terminating on the external surface of said element for passage of yarn thereover, a pressure responsive member having a face exposed to the pressure in said chamber, a mechanism adapted when actuated to arrest the travel of yarn and means controlled by said pressure responsive member for actuating said mechanism when the pressure in said chamber exceeds a predetermined value corresponding to a predetermined increase in the diameter of yarn passing over the surface of said element.

4. The device according to claim 3 wherein the outlet passage terminates in a groove in the external surface of said element, the groove serving to guide the yarn in its passage over the surface of the element.

5-. The device according to claim 3 wherein said element includes at least one other outlet passage and means whereby the connection between said first mentioned outlet passage and said chamber may be broken and said other outlet passage connected to said chamber, said other outlet passage when connected with said chamber terminating on the external surface of the element for passage of yarn thereover.

6. The device according to claim 3 wherein said mechanism includes a hammer biased into yarn holding position and latch means normally restraining movement of said hammer, said means controlled by said pressure responsive element operating to actuate said mechanism by tripping said latch means.

7. A pneumatic slub catcher comprising in combination an element cut away at one end to form a reentrant chamber, a diaphragm secured to said element and forming a moveable wall of the chamber, said element being provided with a restricted inlet passage for air under pressure communicating with said chamber and with an outlet passage terminating in an orifice on the surface of the element for travel of yarn thereover, a plunger biased into engagement with said diaphragm, a latch controlled by said plunger for release upon a predetermined movement of the plunger, and yarn holding mechanism actuated upon release of said latch.

8. The slub catcher according to claim '7 wherein said element is provided with a second outlet passage terminating in an orifice for travel of yarn thereover, said passages being closely spaced and terminating in a smooth peripheral arcuate groove in the surface of the element serving as a guide for yarn in transit through the device.

9. The slub catcher according to claim 7 wherein said element is provided with additional outlet passages each adapted to be brought into exclusive communication with said chamber, each of said outlet passages terminating in an orifice on the surface of said element, each of anism is actuated when a said orifices, when the associated passage is brought into communication with said chamber, being in a position for passage of yarn thereover.

10. A pneumatic slub catcher comprising a base, a bracket secured thereto, a pair of annular members mounted on said bracket, a plate secured to said base and having asurface for passage of yarn thereover, a hammer slidably mounted on said base adjacent said surface, means biasing said hammer toward said surface, releasable means normally holding said hammer in retracted position, a diaphragm secured at its periphery between said annular members, an element secured to one of said members and having a chamber formed therein communicating with one wall of said diaphragm, said element being provided with a restricted air inlet passage communicating with said chamber and with an air outlet passage leading from said chamber and terminatin in an orifice on the surface of the element for passage of yarn thereover, a frame member secured to the other of said annular members, a plunger slidably mounted in said frame member with one end engaging said diaphragm, a lever pivotally mounted at one end on said frame member and linked to said plunger and means carried by the free endof said lever for releasing said restraining means upon predetermined angular movement of said lever.

11. The slub catcher according to claim 10 including a yarn tension device mounted on said base in the path of travel of yarn to the surface of said element and a fixed yarn guide mounted on said base in the path of travel of yarn from the surface of said plate.

12. The slub catcher according to claim 10 wherein said element is removably secured to the annula member.

13. The slub catcher according to claim 10 wherein said element is provided with a second outlet passage leading from said chamber and terminating in an orifice adjacent the first mentioned orifice and in the path of travel of yarn.

14. A yarn monitor device comprising in combination, an element havin a smoothly rounded surface for passage of yarn thereover, a chamber within said element for fluid under pressure, said element being provided with a restricted inlet passage leading to said chamber and with an outlet passage leading from said chamber and terminating at said surface, mechanism adapted, when actuated, to signify the occurrence of a slub in yarn travelling over said surface and means sensitive to th pressure in said chamber for ac tuating said mechanism when the pressure in said chamber exceeds a predetermined value, whereby, when air under pressure is delivered to said chamber and bleeds to the atmosphere around yarn travelling at a constant rate over the end of the outlet passage on saidsurface, said mechslub of a length greater than a predetermined length and of a diameter greater than a predetermined value travels over I the end of the outlet passage.

WILMER c. ANDERSON. REFERENCES CITED.

The following references are of record in the file of this patent:

UNITED STATES PATENTS Number I Name Date 2,026,155 Abbott Dec, 31, 1935 2,077,525 Mennesson Apr. 20, 1937 2,295,399 Hanna Sept. 8, 1942 

